Predictability of the UK variant Creutzfeldt-Jakob disease epidemic.

Back-calculation analysis of the variant Creutzfeldt-Jakob disease epidemic in the United Kingdom is used to estimate the number of infected individuals and future disease incidence. The model assumes a hazard of infection proportional to the incidence of bovine spongiform encephalopathy in the United Kingdom and accounts for precautionary control measures and very wide ranges of incubation periods. The model indicates that current case data are compatible with numbers of infections ranging from a few hundred to several millions. In the latter case, the model suggests that the mean incubation period must be well beyond the human life-span, resulting in disease epidemics of at most several thousand cases.